CVE-2026-52991 (GCVE-0-2026-52991)

Vulnerability from cvelistv5 – Published: 2026-06-24 16:29 – Updated: 2026-08-20 12:31
VLAI
Title
sched/psi: fix race between file release and pressure write
Summary
In the Linux kernel, the following vulnerability has been resolved: sched/psi: fix race between file release and pressure write A potential race condition exists between pressure write and cgroup file release regarding the priv member of struct kernfs_open_file, which triggers the uaf reported in [1]. Consider the following scenario involving execution on two separate CPUs: CPU0 CPU1 ==== ==== vfs_rmdir() kernfs_iop_rmdir() cgroup_rmdir() cgroup_kn_lock_live() cgroup_destroy_locked() cgroup_addrm_files() cgroup_rm_file() kernfs_remove_by_name() kernfs_remove_by_name_ns() vfs_write() __kernfs_remove() new_sync_write() kernfs_drain() kernfs_fop_write_iter() kernfs_drain_open_files() cgroup_file_write() kernfs_release_file() pressure_write() cgroup_file_release() ctx = of->priv; kfree(ctx); of->priv = NULL; cgroup_kn_unlock() cgroup_kn_lock_live() cgroup_get(cgrp) cgroup_kn_unlock() if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv The cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards the memory deallocation of of->priv performed within cgroup_file_release(). However, the operations involving of->priv executed within pressure_write() are not entirely covered by the protection of cgroup_mutex. Consequently, if the code in pressure_write(), specifically the section handling the ctx variable executes after cgroup_file_release() has completed, a uaf vulnerability involving of->priv is triggered. Therefore, the issue can be resolved by extending the scope of the cgroup_mutex lock within pressure_write() to encompass all code paths involving of->priv, thereby properly synchronizing the race condition occurring between cgroup_file_release() and pressure_write(). And, if an live kn lock can be successfully acquired while executing the pressure write operation, it indicates that the cgroup deletion process has not yet reached its final stage; consequently, the priv pointer within open_file cannot be NULL. Therefore, the operation to retrieve the ctx value must be moved to a point *after* the live kn lock has been successfully acquired. In another situation, specifically after entering cgroup_kn_lock_live() but before acquiring cgroup_mutex, there exists a different class of race condition: CPU0: write memory.pressure CPU1: write cgroup.pressure=0 =========================== ============================= kernfs_fop_write_iter() kernfs_get_active_of(of) pressure_write() cgroup_kn_lock_live(memory.pressure) cgroup_tryget(cgrp) kernfs_break_active_protection(kn) ... blocks on cgroup_mutex cgroup_pressure_write() cgroup_kn_lock_live(cgroup.pressure) cgroup_file_show(memory.pressure, false) kernfs_show(false) kernfs_drain_open_files() cgroup_file_release(of) kfree(ctx) of->priv = NULL cgroup_kn_unlock() ... acquires cgroup_mutex ctx = of->priv; // may now be NULL if (ctx->psi.trigger) // NULL dereference Consequently, there is a possibility that of->priv is NULL, the pressure write needs to check for this. Now that the scope of the cgroup_mutex has been expanded, the original explicit cgroup_get/put operations are no longer necessary, this is because acquiring/releasing the live kn lock inherently executes a cgroup get/put operation. [1] BUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 Call Trace: pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43 ---truncated---
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0e94682b73bfa6c44c98af7a26771c9c08c055d5 , < 03dc070fa0fc3cb4068693f468ccd5f8a7e58282 (git)
Affected: 0e94682b73bfa6c44c98af7a26771c9c08c055d5 , < d4352c0709bfd38c752fccbde7fd72a82ac78f23 (git)
Affected: 0e94682b73bfa6c44c98af7a26771c9c08c055d5 , < a5b98009f16d8a5fb4a8ff9a193f5735515c38fa (git)
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Linux Linux Affected: 5.2
Unaffected: 0 , < 5.2 (semver)
Unaffected: 6.18.33 , ≤ 6.18.* (semver)
Unaffected: 7.0.10 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
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Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/psi: fix race between file release and pressure write\n\nA potential race condition exists between pressure write and cgroup file\nrelease regarding the priv member of struct kernfs_open_file, which\ntriggers the uaf reported in [1].\n\nConsider the following scenario involving execution on two separate CPUs:\n\n   CPU0\t\t\t\t\tCPU1\n   ====\t\t\t\t\t====\n\t\t\t\t\tvfs_rmdir()\n\t\t\t\t\tkernfs_iop_rmdir()\n\t\t\t\t\tcgroup_rmdir()\n\t\t\t\t\tcgroup_kn_lock_live()\n\t\t\t\t\tcgroup_destroy_locked()\n\t\t\t\t\tcgroup_addrm_files()\n\t\t\t\t\tcgroup_rm_file()\n\t\t\t\t\tkernfs_remove_by_name()\n\t\t\t\t\tkernfs_remove_by_name_ns()\n vfs_write()\t\t\t\t__kernfs_remove()\n new_sync_write()\t\t\tkernfs_drain()\n kernfs_fop_write_iter()\t\tkernfs_drain_open_files()\n cgroup_file_write()\t\t\tkernfs_release_file()\n pressure_write()\t\t\tcgroup_file_release()\n ctx = of-\u003epriv;\n\t\t\t\t\tkfree(ctx);\n \t\t\t\t\tof-\u003epriv = NULL;\n\t\t\t\t\tcgroup_kn_unlock()\n cgroup_kn_lock_live()\n cgroup_get(cgrp)\n cgroup_kn_unlock()\n if (ctx-\u003epsi.trigger)  // here, trigger uaf for ctx, that is of-\u003epriv\n\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\nthe memory deallocation of of-\u003epriv performed within cgroup_file_release().\nHowever, the operations involving of-\u003epriv executed within pressure_write()\nare not entirely covered by the protection of cgroup_mutex. Consequently,\nif the code in pressure_write(), specifically the section handling the\nctx variable executes after cgroup_file_release() has completed, a uaf\nvulnerability involving of-\u003epriv is triggered.\n\nTherefore, the issue can be resolved by extending the scope of the\ncgroup_mutex lock within pressure_write() to encompass all code paths\ninvolving of-\u003epriv, thereby properly synchronizing the race condition\noccurring between cgroup_file_release() and pressure_write().\n\nAnd, if an live kn lock can be successfully acquired while executing\nthe pressure write operation, it indicates that the cgroup deletion\nprocess has not yet reached its final stage; consequently, the priv\npointer within open_file cannot be NULL. Therefore, the operation to\nretrieve the ctx value must be moved to a point *after* the live kn\nlock has been successfully acquired.\n\nIn another situation, specifically after entering cgroup_kn_lock_live()\nbut before acquiring cgroup_mutex, there exists a different class of\nrace condition:\n\nCPU0: write memory.pressure               CPU1: write cgroup.pressure=0\n===========================\t\t  =============================\n\nkernfs_fop_write_iter()\n kernfs_get_active_of(of)\n pressure_write()\n   cgroup_kn_lock_live(memory.pressure)\n     cgroup_tryget(cgrp)\n     kernfs_break_active_protection(kn)\n     ... blocks on cgroup_mutex\n\n                                     \t  cgroup_pressure_write()\n                                     \t  cgroup_kn_lock_live(cgroup.pressure)\n                                     \t  cgroup_file_show(memory.pressure, false)\n                                     \t    kernfs_show(false)\n                                     \t      kernfs_drain_open_files()\n                                     \t        cgroup_file_release(of)\n                                     \t          kfree(ctx)\n                                     \t            of-\u003epriv = NULL\n                                     \t  cgroup_kn_unlock()\n\n   ... acquires cgroup_mutex\n   ctx = of-\u003epriv;        // may now be NULL\n   if (ctx-\u003epsi.trigger)  // NULL dereference\n\nConsequently, there is a possibility that of-\u003epriv is NULL, the pressure\nwrite needs to check for this.\n\nNow that the scope of the cgroup_mutex has been expanded, the original\nexplicit cgroup_get/put operations are no longer necessary, this is\nbecause acquiring/releasing the live kn lock inherently executes a\ncgroup get/put operation.\n\n[1]\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\nCall Trace:\n pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\n cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\n---truncated---"
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      "version": "5"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-52991\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-06-24T17:17:09.953\",\"lastModified\":\"2026-08-20T13:19:00.250\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nsched/psi: fix race between file release and pressure write\\n\\nA potential race condition exists between pressure write and cgroup file\\nrelease regarding the priv member of struct kernfs_open_file, which\\ntriggers the uaf reported in [1].\\n\\nConsider the following scenario involving execution on two separate CPUs:\\n\\n   CPU0\\t\\t\\t\\t\\tCPU1\\n   ====\\t\\t\\t\\t\\t====\\n\\t\\t\\t\\t\\tvfs_rmdir()\\n\\t\\t\\t\\t\\tkernfs_iop_rmdir()\\n\\t\\t\\t\\t\\tcgroup_rmdir()\\n\\t\\t\\t\\t\\tcgroup_kn_lock_live()\\n\\t\\t\\t\\t\\tcgroup_destroy_locked()\\n\\t\\t\\t\\t\\tcgroup_addrm_files()\\n\\t\\t\\t\\t\\tcgroup_rm_file()\\n\\t\\t\\t\\t\\tkernfs_remove_by_name()\\n\\t\\t\\t\\t\\tkernfs_remove_by_name_ns()\\n vfs_write()\\t\\t\\t\\t__kernfs_remove()\\n new_sync_write()\\t\\t\\tkernfs_drain()\\n kernfs_fop_write_iter()\\t\\tkernfs_drain_open_files()\\n cgroup_file_write()\\t\\t\\tkernfs_release_file()\\n pressure_write()\\t\\t\\tcgroup_file_release()\\n ctx = of-\u003epriv;\\n\\t\\t\\t\\t\\tkfree(ctx);\\n \\t\\t\\t\\t\\tof-\u003epriv = NULL;\\n\\t\\t\\t\\t\\tcgroup_kn_unlock()\\n cgroup_kn_lock_live()\\n cgroup_get(cgrp)\\n cgroup_kn_unlock()\\n if (ctx-\u003epsi.trigger)  // here, trigger uaf for ctx, that is of-\u003epriv\\n\\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\\nthe memory deallocation of of-\u003epriv performed within cgroup_file_release().\\nHowever, the operations involving of-\u003epriv executed within pressure_write()\\nare not entirely covered by the protection of cgroup_mutex. Consequently,\\nif the code in pressure_write(), specifically the section handling the\\nctx variable executes after cgroup_file_release() has completed, a uaf\\nvulnerability involving of-\u003epriv is triggered.\\n\\nTherefore, the issue can be resolved by extending the scope of the\\ncgroup_mutex lock within pressure_write() to encompass all code paths\\ninvolving of-\u003epriv, thereby properly synchronizing the race condition\\noccurring between cgroup_file_release() and pressure_write().\\n\\nAnd, if an live kn lock can be successfully acquired while executing\\nthe pressure write operation, it indicates that the cgroup deletion\\nprocess has not yet reached its final stage; consequently, the priv\\npointer within open_file cannot be NULL. Therefore, the operation to\\nretrieve the ctx value must be moved to a point *after* the live kn\\nlock has been successfully acquired.\\n\\nIn another situation, specifically after entering cgroup_kn_lock_live()\\nbut before acquiring cgroup_mutex, there exists a different class of\\nrace condition:\\n\\nCPU0: write memory.pressure               CPU1: write cgroup.pressure=0\\n===========================\\t\\t  =============================\\n\\nkernfs_fop_write_iter()\\n kernfs_get_active_of(of)\\n pressure_write()\\n   cgroup_kn_lock_live(memory.pressure)\\n     cgroup_tryget(cgrp)\\n     kernfs_break_active_protection(kn)\\n     ... blocks on cgroup_mutex\\n\\n                                     \\t  cgroup_pressure_write()\\n                                     \\t  cgroup_kn_lock_live(cgroup.pressure)\\n                                     \\t  cgroup_file_show(memory.pressure, false)\\n                                     \\t    kernfs_show(false)\\n                                     \\t      kernfs_drain_open_files()\\n                                     \\t        cgroup_file_release(of)\\n                                     \\t          kfree(ctx)\\n                                     \\t            of-\u003epriv = NULL\\n                                     \\t  cgroup_kn_unlock()\\n\\n   ... acquires cgroup_mutex\\n   ctx = of-\u003epriv;        // may now be NULL\\n   if (ctx-\u003epsi.trigger)  // NULL dereference\\n\\nConsequently, there is a possibility that of-\u003epriv is NULL, the pressure\\nwrite needs to check for this.\\n\\nNow that the scope of the cgroup_mutex has been expanded, the original\\nexplicit cgroup_get/put operations are no longer necessary, this is\\nbecause acquiring/releasing the live kn lock inherently executes a\\ncgroup get/put operation.\\n\\n[1]\\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\\nCall Trace:\\n pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\\n cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\\n---truncated---\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"kernel/cgroup/cgroup.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"0e94682b73bfa6c44c98af7a26771c9c08c055d5\",\"lessThan\":\"03dc070fa0fc3cb4068693f468ccd5f8a7e58282\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0e94682b73bfa6c44c98af7a26771c9c08c055d5\",\"lessThan\":\"d4352c0709bfd38c752fccbde7fd72a82ac78f23\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0e94682b73bfa6c44c98af7a26771c9c08c055d5\",\"lessThan\":\"a5b98009f16d8a5fb4a8ff9a193f5735515c38fa\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"kernel/cgroup/cgroup.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.2\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.2\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.33\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0.10\",\"lessThanOrEqual\":\"7.0.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"affectedData\":[{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 10\",\"defaultStatus\":\"affected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:10\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 6\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:6\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 7\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:7\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 7\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel-rt\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:7\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 8\",\"defaultStatus\":\"affected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:8\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 8\",\"defaultStatus\":\"affected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel-rt\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:8\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 9\",\"defaultStatus\":\"affected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:9\"]},{\"vendor\":\"Red Hat\",\"product\":\"Red Hat Enterprise Linux 9\",\"defaultStatus\":\"affected\",\"collectionURL\":\"https://access.redhat.com/downloads/content/package-browser/\",\"packageName\":\"kernel-rt\",\"cpes\":[\"cpe:/o:redhat:enterprise_linux:9\"]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.0,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.0,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-362\"}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-367\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.2\",\"versionEndExcluding\":\"6.18.33\",\"matchCriteriaId\":\"E61720BB-33AA-4F7D-842F-6F12F9E9FD8C\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.19\",\"versionEndExcluding\":\"7.0.10\",\"matchCriteriaId\":\"A13475D2-59BF-4716-94B5-7C1D239A2CF4\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"B1EF7059-E670-45F4-B422-54C40FA86390\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/03dc070fa0fc3cb4068693f468ccd5f8a7e58282\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/a5b98009f16d8a5fb4a8ff9a193f5735515c38fa\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/d4352c0709bfd38c752fccbde7fd72a82ac78f23\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:57251\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:57252\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:57253\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/errata/RHSA-2026:57254\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\"},{\"url\":\"https://access.redhat.com/security/cve/CVE-2026-52991\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://bugzilla.redhat.com/show_bug.cgi?id=2492403\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"tags\":[\"Issue Tracking\",\"Third Party Advisory\"]},{\"url\":\"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52991.json\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"tags\":[\"Third Party Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-08-20T07:58:54+00:00",
      "cve": "CVE-2026-52991",
      "id": "CVE-2026-52991",
      "initial_release_date": "2026-06-24T00:00:00+00:00",
      "product_status:fixed": "762",
      "product_status:known_affected": "22",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: sched/psi: fix race between file release and pressure write",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52991.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-21T00:57:19Z",
      "cve": "CVE-2026-52991",
      "id": "CVE-2026-52991",
      "initial_release_date": "2026-06-26T02:14:19Z",
      "product_status:first_fixed": "98",
      "product_status:known_affected": "216",
      "product_status:known_not_affected": "67",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-52991",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-52991.json",
      "version": "7"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.